Method of making multidimensional polyesters

ABSTRACT

The yield of fully substituted, multidimensional aromatic hubs in the condensation of hydroxyl and acid halide functionalities is improved by adding a thallium catalyst, such as thallium ethoxide (T1-OC 2  H 5 ), in the solvent.

REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application based upon U.S.patent application Ser. No. 07/176,518, filed Apr. 1, 1988, which was acontinuation-in-part application based upon U.S. patent application Ser.No. 06/810,817, filed Dec. 17, 1985, which was a continuation-in-partapplication based upon U.S. patent application Ser. No. 06/726,258,filed Apr. 23, 1985, all now abandoned.

TECHNICAL FIELD

The present invention relates to a method for making multidimensionalpolyesters using thallium ethoxide as a catalyst.

BACKGROUND OF THE INVENTION

In our earlier applications we proposed the condensation of hydroxyl(--OH) and carboxylic acid (--COOH) or carboxylic acid halides (--COX)on an aromatic hub having at least three such functionalities. Thecondensation occurred in a suitable solvent, such as DMAC, under aninert atmosphere in the presence of triethylamine (TEA). We have foundthat, when reacting, for example, phloroglucinol with an acid chlorideend cap of the formula: ##STR1## in DMAC and TEA that the resultingproduct is a mixture of ##STR2## The condensation is difficult to driveto completion (i.e., replacement of all the --OH groups) to yield thedesired product (I). The yield of fully reacted multidimensional ester(I) can be improved, however, by replacing the TEA with thalliumethoxide (T1-OC₂ H₅).

The present invention is a method to improve the yield offully-substituted multidimensional polyesters, particularly polyesteroligomers having a trisubstituted phenylene hub and crosslinkinghydrocarbon unsaturation at the end of each arm linked to the hub. Themethod involves conducting the esterification reaction in the presenceof a thallium catalyst, such as thallium ethoxide, in a suitable solventunder an inert atmosphere. Preferably, the solvent includes DMAC andTEA.

BEST MODE CONTEMPLATED FOR THE PRESENT INVENTION

The yield of multidimensional polyesters can be improved by replacingtriethylamine (TEA) in the condensation solution with thallium ethoxide(T1-OC₂ H₅) as a catalyst. Since the polyester oligomers that aresynthesized are often used without isolation of products, we believethat the new product, richer in product (I) [i.e. the trulymultidimensional ester] will yield better composites than are achievedwith the multidimensional (I) and linear (II) blend made using TEA as acatalyst.

The method of the present invention is equally applicable to use of anacid halide hub such as cyuranic acid chloride with a mono- ordifunctional imidophenol end cap monomer. Chain-extension can beachieved, also, by including dialcohols, diacid halides, or both in thecondensation mixture.

We believe that TI-OC₂ H₅ will produce a higher yield of thetri-substituted hub. If the hub has more than three reactive hydroxyl oracid halide functionalities, the thallium ethoxide catalyst will promotemore complete reaction (or substitution) than TEA.

While thallium ethoxide is preferred, it is possible that any loweralkoxy substituent on the metal will be active as a catalyst. That is,methoxy, propoxy, isopropoxy, n-butoxy, phenoxy, or the like may alsodisplay catalytic activity.

Accordingly, the present invention relates to the catalysis of the--OH/--COX or --OH/--COOH condensation with a thallium catalyst, and,particularly, to the preparation of multidimensional polyesters by thecondensation of Ar.paren open-st.Q)_(w) with a corresponding alcohol(--OH), acid (--COOH), or acid halide (--COX) in a suitable solventunder an inert atmosphere with or without heating in the presence ofthallium ethoxide,

wherein

Ar=an aromatic radical of valency w;

w=an integer greater than or equal to 3; and

Q=--OH, --COOH, or --COX.

The aromatic radical will generally be phenyl or azalinyl, being theresidue, for example of phloroglucinol or cyanuric acid chloride. Thosecompounds described in U.S. Pat. Nos. 4,617,390 or 4,709,008 may also beused as hubs, and amine compounds can be reacted with an acid anhydrideto form polycarboxylic acids that are suitable hubs. Triaminobenzene orthe polyamines of U.S. Pat. No. 4,574,152 are suitable reactants(precursors) in this context.

The simplest oligomers can be prepared by condensing about 1 mole of thehub with a crosslinking end cap monomer of the formula:

wherein

.0.=phenyl;

P=--COX, if the hub is a polyol, or --OH, if the hub is a polybasicacid;

i=1 or 2;

D=an unsaturated hydrocarbon radical that generally includes a segmentselected from the group consisting of: ##STR3## R₁ =lower alkyl, aryl,substituted alkyl, substituted aryl, lower alkoxy, aryloxy, halogen, ormixtures thereof;

G=--O--, --S--, --SO₂ --, --CH₂, --CO--, --CHR--, --SO--, or --CR₂ --;

j=0, 1, or 2;

T=allyl or methallyl;

Me=methyl; and

R=hydrogen, lower alkyl, or phenyl.

These end cap monomers allow the multidimensional polyester oligomers tobe cured into high performance, advanced composites that have usetemperature that exceed (often substantially) their curing temperatures.

The arms of the multimdimensional oligomers can be extended if thereaction solution's components are adjusted. For example, the hub of theformula Ar.paren open-st.Q)_(w) can be simultaneously condensed withR.paren open-st.P)₂ wherein

Ar=an aromatic radical of valency w;

w=a small integer greater than or equal to 3;

Q=--COX, --OH, or --COOH;

R=a divalent hydrocarbon radical, especially a phenoxyphenylsulfone; and

P=--OH, if Q=--COX or --COOH, or --COX or --COOH, if Q=--OH

with a crosslinking end cap manomer of the formula:

    Dd.sub.i --.0.--Q

wherein D, i, .0., or Q are as previously defined.

The dialcohols or diacid halides include those compounds disclosed inU.S. Pat. No. 4,547,553 or in our copending applications.

The reaction solution may include four or more component mixtures butdeleterious or interfering competitive reactions are likely to occur,dictating staged reaction rather than simultaneous condensation. Forexample, Ar.paren open-st.Q)_(w) can be condensed with R.parenopen-st.P)₂ followed by addition of R₁ .paren open-st.Q)₂ and D_(i)--.0.--P to form a multidimensional polyester having extended arms(i.e., arms of relatively high average formula weight).

While preferred embodiments have been described, those skilled in theart will readily recognize alterations, variations, or modificationswhich might be made to the embodiments without departing from theinventive concept. Therefore, the claims should be interpreted liberallywith the support of the full range of equivalents known to those ofordinary skill based upon this description. The claims should be limitedonly as is necessary in view of the pertinent prior art.

We claim:
 1. A method for making multidimensional polyesters comprisingthe step of reacting a compound of the formula: Ar.paren open-st.Q)_(w)whereinAr=a phenylene radical of valency w; w=a small integer greaterthan or equal to 3; Q=--OH or --COX; and X=halogenwith substantially astoichiometric amount of a compound of the formula: R-P wherein R=amonovalent radical; and P=--OH, if Q=--COX or --COX, if Q=--OHin asolvent under an inert atmosphere in the presence of an effective amountof a thallium catalyst.
 2. The method of claim 1 wherein the catalyst isthallium ethoxide.
 3. The method of claim 2 wherein the solventcomprises dimethyl acetamide (DMAC).
 4. The method of claim 2 whereinw=3 and the resulting product is substantially fully substitutedphenylene.
 5. The method of claim 2 wherein R, comprises hydrocarbonunsaturation.
 6. The method of claim 4 wherein R comprises hydrocarbonunsaturation.
 7. The method of claim 1 wherein Ar.paren open-st.Q)_(w)is phloroglucinol.
 8. The method of claim 1 wherein Ar.parenopen-st.Q)_(w) is cyuranic acid chloride.
 9. The product of the processof claim
 1. 10. The product of the process of claim
 2. 11. A method formaking multimdimensional polyester oligomers comprising the step ofsimultaneously condensing about 1 mole of a compound of the formula:Ar.paren open-st.Q)_(w),wherein Ar=an aromatic radical of valency w; w=asmall integer greater than or equal to 3; and Q=--OH or --COX whereinX=halogenwith about w moles of a compound of the formula: R.parenopen-st.P)₂ and about w moles of a compound of the formula: R₁ --Q,wherein R=a divalent hydrocarbon radical; P=--OH, if Q=--COX, or --COX,if Q=--OH; and R₁ =a unsaturated hydrocarbon radical in a solvent underan inert atmosphere in the presence of an effective amount of a thalliumcatalyst.
 12. The product of the process of claim
 11. 13. The method ofclaim 1 wherein R is selected from the group consisting of:

    D.sub.i --.0.--

wherein .0.=phenylene; i=1 or 2; D= ##STR4## R₁ =lower alkyl, aryl,substituted alkyl, substituted aryl, lower alkoxy, aryloxy, halogen, ormixtures thereof; G=--O--, --S--, --SO₂ --, --CH₂ --, --CO--, --CHY--,--SO--, or --CY₂ --; j=0, 1, or 2; T=allyl or methallyl; Me=methyl; andY=any of hydrogen, lower alkyl, or phenyl.
 14. The method of claim 13wherein Ar.paren open-st.Q)_(w) is phloroglucinol.
 15. The method ofclaim 13 wherein Ar.paren open-st.Q)_(w) is cyanuric acid chloride. 16.The method of claim 13 wherein the catalyst is thallium ethoxide. 17.The method of claim 16 wherein the solvent comprises DMAC (dimethylacetamide).
 18. The method of claim 11 wherein R₁ is selected from thegroup consisting of:

    D.sub.i --.0.--

wherein .0.=phenyl; i=1 or 2; D=an unsaturated hydrocarbon radical thatcomprises a segment selected from the group consisting of: ##STR5##V=lower alkyl, aryl, substituted alkyl, substituted aryl, lower alkoxy,aryloxy, halogen, or mixtures thereof; G=--O--, --S--, --SO₂ --, --CH₂--, --CO--, --CHY--, --SO--, or --CY₂ --; j=0, 1, or 2; T=allyl ormethallyl; Me=methyl; and Y=any of hydrogen, lower alkyl, or phenyl. 19.The method of claim 18 wherein the catalyst is thallium ethoxide.
 20. Amethod for making a multidimensional polyester comprising the step ofreacting phloroglucinol with a compound of the formula:

    R--COX

wherein X=halogen; R=D_(i) --.0.--; i=1 or 2; .0.=phenylene; D= ##STR6##R₁ =lower alkyl, aryl, substituted alkyl, substituted aryl, loweralkoxy, aryloxy, halogen, or mixtures thereof; G=--O--, --S--, --SO₂ --,--CH₂ --, --CO--, --CHY--, --SO--, or --C(Y)₂ --; j=0, 1, or 2; T=allylor methallyl; Me=methyl; and Y=any of hydrogen, lower alkyl, or phenylto form substantially completely substituted polyester oligomers of theformula:

    .0..paren open-st.OOC--.0.--D.sub.i).sub.3

the reaction being catalyzed by thallium ethoxide in a solventcomprising dimethyl acetamide (DMAC), under an inert atmosphere in thepresence of triethylamine.
 21. A method for making a substantiallyfully-substituted multidimensional polyester at high yield, comprisingthe steps of:reacting a compound of the formula: Ar.paren open-st.Q)_(w)with substantially a stoichiometric amount of a second compound having afunctionality reactive with Q to form an ester the reaction occurring inthe presence of a catalytically effective amount of thallium ethoxide ina suitable solvent, including dimethyl acetamide, under an inertatmosphere in the presence of triethylamine, the reaction yieldingessentially fully substituted Ar, wherein Ar=phenylene or a residue ofcyanuric acid halide; Q=--OH or --COX; and X=halogen.